Pathologists are uniquely positioned to contribute to cancer research. Their familiarity with disease classifications and pathogenesis, physical manifestations of tumors in tissue and clinical challenges in cancer care mean that these investigators can provide important perspectives in developing experimental models that recapitulate key aspects of human disease. Johns Hopkins University School of Medicine has a history of excellence in academic pathology, and today has state-of-the-art hospital and research environments attracting many talented and hard-working clinical trainees. Many have gone on to become nationally and internationally prominent researchers and pathologists. We have high confidence in our ability to continue to recruit some of the nation's brightest, most dedicated future physician-scientists to our department. The proposed training program, Opportunities for Pathology Trainees In Cancer research (OPTIC), will hugely augment our ability to develop these fellows, providing support for entirely `protected' research time during formative years as they initiate research projects and set directions for work that will define the outset of their independent careers. We expect to recruit 2 postdoctoral fellows annually, each entering the program at PGY2 or PGY4 for a total of up to 4 fellows by Year 2. Each trainee will select a research mentor from participating faculty - a stellar group recruited from the full spectrum of cancer research fields at the institution. All are accomplished investigators with an expertise in experimental cancer research and strong track records of laboratory based mentorship. In addition to research, trainees will participate in newly established, dedicated didactics and workshops to develop skills for their independent careers, and will enroll in other course work tailored to their individual interests and chosen to complement their previous experiences. Each trainee will convene meetings of an Individual Progress Committee, members of which will provide feedback on their progress, recommend specific near-term research goals and training activities, and generally be available as career mentors and advocates. We expect that fellows will leave the program poised for transitions to mentored and independent faculty positions in academic pathology departments and fully prepared to conduct high impact cancer research.